What is "kranioi"

Kranioi or Cranii was an ancient Greek city on the island of Cephalonia. Its ruins are located near Argostoli. According to Thucydides' History of the Peloponnesian War, Krani was settled by the Messenians and Helot deserters of Sparta at the discretion of Athens. As part of the negotiations with Sparta after the "50 Years Truce" was signed, these people were moved from their garrison at Pylos where they were involved in a blockade of the troops on the island in the bay of Pylos. They were relieved by Athenian troops who then garrisoned the bay.